Vehicular rotary electrical switch assembly with removable,interposed non-conductive plug kill switch means

ABSTRACT

Each of the illustrated electrical switches comprises a contactor plate which is rotatable with a carriage in a casing. The contactor plate is biased by resilient means toward a plurality of contact points mounted in one end of the casing opposite the contactor plate. One of the contact points is engageable with a plurality of recesses or undulations in the contactor plate to provide a detaining action whereby the contactor plate is detained in a plurality of angularly spaced positions. Such contact point is in electrical contact with the contactor plate in each of such positions. The contactor plate also has contact segments which are engageable with other contact points as the contactor is rotated. In one embodiment, a pull pin or other stop member is removably mounted in the casing to hold the contactor plate away from one or more contact points in at least one position of the switch. The contactor may have recessed members or undulations which are opposite such contact points. The removal of the stop member releases the contactor plate for movement by the resilient means so as to bring the recessed members into engagement with the contact points. The removable pull pin or stop member may be employed as as a safety feature on a snowmobile or other vehicle whereby the pull pin may be connected by means of a cord or the like to the body or clothing of the rider so that the pull pin will be pulled out of the switch if the rider falls off the vehicle. The resulting closure of the switch may be employed to stop the engine of the vehicle.

United States Patent [191 Cobb et al.

[ 1 Nov. 19,1974

[ 1 VEHICULAR ROTARY ELECTRICAL SWITCH ASSEMBLY WITH REMOVABLE,INTERPOSED NON-CONDUCTIVE PLUG KILL SWITCH MEANS Inventors: Jesse M.Cobb, Glenview; William J.

Schaad, Winnetka, both of 111.

Assignee: Indak Manufacturing Corp.,

Northbrook, 111.

Filed: Aug. 1, 1973 'Appl. No.: 384,603

[56] References Cited UNITED STATES PATENTS 8/1955 Miller 200/11 C1/1957 Jacobi 200/11 C 12/1964 Cobb et a]. ZOO/l1 J 2/1970 Schink et a1.200/11 C Primary Examiner-James R. Scott Attorney, Agent, orFirm-Burmeister, Palmatier & Hamby ABSTRACT Each of the illustratedelectrical switches comprises a contactor plate which is rotatable witha carriage in a casing. The contactor plate is biased by resilient meanstoward a plurality of contact points mounted in one end of the casingopposite the contactor plate. One of the contact points is engageablewith a plurality of recesses or undulations in the contactor plate toprovide a detaining action whereby the contactor plate is detained in aplurality of angularly spaced positions. Such contact point is inelectrical contact with the contactor plate in each of such positions.The contactor plate also has contact segments which are engageable withother contact points as the contactor is rotated. In one embodiment, apull pin or other stop member is removably mounted in the casing to holdthe contactor plate away from one or more contact points in at least oneposition of the switch. The contactor may have recessed members orundulations which are opposite such contact points. The removal of thestop member releases the contactor plate for movement by the resilientmeans so as to bring the recessed members ,into engagement with thecontact Points T e i y r tst p .ms l stmay be employed as as a safetyfeature on a snowmobile or other vehicle whereby the pull pin may beconnected by means of a cord or the like to the body or clothing of therider so that the pull pin will be pulled out of the switch if the riderfalls off the vehicle. The resulting closure of the switch may beemployed to stop the engine of the vehicle.

45 llillii; i i....11lii SHEET 2 OF 4 F261 5 FIG. 6

VEHICULAR ROTARY ELECTRICAL SWITCH ASSEMBLY WITH REMOVABLE, INTERPOSEDNON-CONDUCTIVE PLUG KILL SWITCH MEANS This invention relates toelectrical switches preferably of the rotary type.

One object of the present invention is to provide rotary electricalswitches which will find various applications, but are particularly welladapted for use on snowmobiles or other vehicles.

A further object is to provide new and improved rotary electricalswitches which may be employed very advantageously on snowmobiles orother vehicles to provide a kill switch which disables the ignitionsystem of the vehicle engine, a headlight dimmer switch or the like.

Another object is to provide a new and improved rotary switch having asafety feature comprising a removable pull pin or other member which maybe connected by means of a cord or the like to the body or clothing ofthe vehicle operator so that the pin will be pulled from the switch ifthe operator falls off the vehicle. The removal of the pin causes theswitch to operate so as to stop the vehicle.

It is a further object to provide a new and improved rotary switch ofthe foregoing character in which the safety feature provided by the pullpin is incorporated into a rotary kill switch which may be operatedmanually to stop the vehicle.

Further objects, advantages and features of the present invention willappear from the following description, taken with the accompanyingdrawings, in which:

FIG. 1 is a plan view showing a rotary kill switch to be described as anillustrative embodiment of the present invention, the switch beingmounted on the handlebar of a snowmobile or other vehicle.

FIG. 2 is an end view of the handlebar grip taken generally as indicatedby the line 22 in FIG. 1.

FIG. 3 is a front view showing the safety pull pin removed from theswitch.

FIG. 4 is an enlarged rear view of the switch.

FIG. 5 is a sectional view taken generally along the line 55 in FIG. 1.

FIG. 6 is a fragmentary view similar to FIG. 5, but showing variouscomponents in elevation.

FIG. 7 is a view similar to FIG. 6 with the safety pull pin removed.

FIG. 8 is a section taken generally along the line 88 in FIG. 5.

FIG. 9 is a diagrammatic developed view showing the switch contactor inits RUN position.

FIG. 10 is a view similar to FIG. 9, but showing the contactor in one ofits OFF or KILL positions.

FIG. 11 is a view similar to FIG. 9, but showing the effect of removingthe pull pin.

FIG. 12 is a front view of the casing of the switch.

FIG. 13 is a rear view of the combined carriage and knob.

FIG. 14 is a front view showing the member which supports the contactpoints.

FIG. 15 is a front viewof the contactor.

FIG. 16 is a front view of a headlight dimmer switch constituting amodified embodiment of the present invention.

FIG. I7 is a rear view of the headlight dimmer switch.

FIG. 18 is a front view of the contact points and their supportingmember employed in the switch of FIG. 16.

FIG. 19 is a front view of the contactor for the switch of FIG. 16.

FIGS. 20 and 21 are diagrammatic developed views showing the twooperating positions of the contactor for the switch of FIG. 16.

As just indicated. FIG. I illustrates a preferred embodiment of thepresent invention in the form of a rotary switch 10 which will find manyapplications. but is particularly well adapted to serve as a kill switchfor a snowmobile or some other vehicle. The kill switch I0 is operativeto turn off the engine by inactivating the ignition system. In ths usualarrangement, the kill switch 10 may be operated to short circuit theprimary circuit of the magneto employed in the ignition system.

As shown in FIG. 1, the kill switch 10 is adapted to be mounted on thehandlebar 12 of the snowmobile or other vehicle. In this case, theswitch 10 is incorporated into a grip member 14 adapted to be mounted onthe handlebar 12. The grip member 14 also includes a handgrip 16 adaptedto be grasped by the operator. Thus, the switch 10 is convenientlypositioned for quick and easy operation.

As shown, the kill switch 10 has a rotary knob or handle 18 which can beoperated to three positions: a central RUN position, shown in full linesin FIG. 1; and two OFF positions, shown in broken lines. The OFFpositions are angularly spaced in opposite directions from the RUNposition. With this arrangement, the engine can be stopped by turningthe knob 18 in either direction from the RUN position. In this way, notime will be lost in attempting to turn the knob 18 in the wrongdirection. This mode of operation is an important safety feature.

The illustrated kill switch 10 has a casing 20, which is adapted to bereceived in a recess 22 formed between two portions 24 and 26 of thegrip member 14. Screws or other fasteners 28 may be employed to fastenthe portions 24 and 26 together.

As an added safety feature, the kill switch 10 is provided with a pullpin or other removable member 30 which normally extends into the casing20 of the switch 10, but may be pulledout of the casing, as shown inFIG. 3. The removal of the pin 30 effectively operates the switch 10 toanother OFF position in which the ignition is inactivated.

The pin 30 is provided with a pull cord or other ten sion element 32which may be connected to the body or the clothing of the operator. Inthis way, the pin 30 will be pulled out of the switch 10 if the operatorfalls off the vehicle, or if the vehicle travels away from the operatorwhile he is temporarily dismounted. The removal of the pin 30 causes theengine to stop so that the vehicle will come to a halt. The provision ofthe pull pin 30 thus makes it possible to prevent accidents whichotherwise might occur due to movement of the vehicle without the rider.

The kill switch 10 preferably comprises a contactor 34 (FIGS. 5-8) whichis rotatable within the casing 20. Various means may be provided torotate the contactor 34. In this case, the contactor 34 is mounted onand rotatable with a carriage 36 which is combined with the knob 18.

The contactor 34 is engageable with a plurality of fixed contacts whichare mounted in the casing 20, preferably on an end plate or member 38,which may be made of an electrically insulating material, such assuitable plastic. The contact supporting member 38 may be mounted withinan opening 40 formed in the rear end of the casing 20. In this case, thecasing 20 is also preferably made of a suitable plastic resinousmaterial. The contact supporting member 38 is suitably secured withinthe opening 40. It is preferred to fasten the member 38 to the casing 20by ultrasonic welding or heat sealing. However, cement or otherfastening means may be employed.

The electrical contacts on the member 38 preferably take the form of aplurality of contact points. In this case, there are three such contactpoints 41, 42 and 43. However, it will be understoodtthat thearrangement and number of the contact points may be varied. The contactpoints 41, 42 and 43 project forwardly from the member 38 and into thecasing 20.

In this case, electrical leads 42a and 43a are connected to the contactpoints 42 and 43. A lead may also be connected to the contact point 41,but in this case, no such lead is required.

The contactor 34 may assume various forms, but is illustrated as beinggenerally in the form of a circular plate made of conductive material,such as copper or some other metal. The illustrated contactor 34 isformed with a central, generally circular opening 44 adapted to receivea generally cylindrical shaft portion 46 of the carriage 36. Thecontactor 34 may have key elements or prongs 48 received in keyways orgrooves 50 formed in the shaft portion 46. In this way, the contactor 34is caused to rotate with the carriage 36.

Various resilient means may be provided to bias the contactor 34rearwardly toward the contact points 41, 42 and 43. Such resilient meansmay take the form of at least one spring, illustrated as a single coilspring 52 acting between the carriage 36 and the contactor 34. Theillustrated spring 52 is mounted around the shaft member 46 between thecontactor 34 and a shoulder 54 on the carriage 36.

The illustrated rotary carriage 36 has an enlarged cylindrical portion56 extending between the knob 18 and the shaft portion 46. Thecylindrical member 56 is rotatably guided within a cylindrical opening58 in the as shown at 70. The washer 68 and the riveted portion 70retain the pilot portion 62 within the opening 66.

The contactor 34 is preferably provided with detent elements adapted tocooperate with one or more of the contact points 41-43. By virtue ofthis detent action, the contactor 34, the carriage 36 and the knob 18are detained in a plurality of angularly spaced positions. In this case,such detent elements take the form of recesses 72a, 72b and 720 formedin the contactor 34.

As shown to best advantage in the developed views of FIGS. 9, l and 11,the contactor 34 is preferably made of sheet metal so that it isadvantageous to form the recesses 72a, 72b and 720 as undulations in thecon tactor. The detent recesses are spaced apart by angular casing 20.In this case, the casing 20 is provided with a flexible resilientsealing lip or flange 60 angling inwardly around the outer end of theopening 58. The lip 60 is biased by its own resilience into sealingengagement with the cylindrical member 58. The lip 60 also providesfrictional resistance to movement of the cylindrical member 56 and keepsit from rattling. The sealing lip 60 is preferably molded integrallywith'the casing 20.

The illustrated carriage 36 is formed with a cylindrical pilot portion62 projecting rearwardly from the shaft portion 46 along the axisthereof. The pilot portion 62 may be rotatably guided within an opening64 formed in the contact supporting member 38.

Suitable means may be provided to retain the carriage 36 within thecasing 20. In this case, the carriage 36 has a reduced end portion 66projecting rearwardly from the pilot portion 62. A washer or disc 68 ismounted on the reduced portion 66, which is then upset or riveted by theapplication of pressure and heat,

intervals corresponding to the desired spacing between the operatingpositions of the switch. In this case, for example, the detent recesses72b and 720 are spaced by about 40 from the recess 72a on opposite sidesthereof.

It will be seen that the contact point 4] acts as a detent projection tocooperate with the detent recesses 72a, 72b and 720. The contact point41 is received in the recess 72a when the knob 'lS of the switch is inits RUN position, as shown in FIG. 1. The contact point 41 is receivedwithin the recesses 72b and 720 when the switch knob 18 is in its twoOFF positions. It will be understood that the contact point 41 is inelectrical engagement with the contactor 34 in all three positions ofthe switch. The spring 52 biases the contactor 34 against the contactpoint 41 to produce resilient resistance to movement of the contactorbetween its various positions.

The angular extent to which the knob 18 can be rotated is limited bystop elements which may be provided on the knob and the casing 20. Asshown in FIG. 13, the rear portion of the knob 18 may be formed with aninwardly directed stop projection 74 adapted to be engaged with stopshoulders 76-and 78 at the opposite ends of a segmental recess 80 formedin the casing 20.

To produce the desired switching functions, the contactor 34 is providedwith one or more contact seg ments or other members which are engageablewith the other contact points. In this case, the contactor 34 has threesuch contact segments 82a, 82b and 82c, which are engageable with thecontact points 42 and 43. Recessed members 84a and 84b are formed in thecontactor 34 between the contact segments 82a, 82b and 82c. As shown,the recessed members 84a and 84b take the form of undulations in thesheet metal contactor 34.

In the RUN positionof FIGS. 8 and 9, the recessed members 840 and 84bare opposite the contact points 42 and 43 so that the contactor 34 isout of engagement with the contact points 42 and 43. The contactor 34 isheld away from the contact points 42 and 43 by stop members 86a and 86b,which might be fixed on the contact supporting member 38,- but in thiscase are elements of the removable pin or member 30. The stop elements86a and 86b are preferably made of an electrically insulating material,such as a suitable resinous plastic. As shown, the stop members 86a and86b are located in the angular interval between the contact points 42and 43.

In the RUN position of the contactor 34, as shown in FIGS. 8 and 9, thestop elements 86a and 86b are engaged by the contact segment 82b of thecontactor 34. The thickness of the stop elements 86a and 86b is suchthat the recessed members 84a and 84b are held away from the contactpoints 42 and 43.

If the contactor 34 is rotated to one of its OFF positions, as shown inFIG. 10, the contact segments 82b and 82a are moved into engagement withthe contact I points 42 and 43, respectively, so that the contactor 34is electrically engaged with both contact points. Thus, the contactor 34forms a closed electrical circuit between the contact points 42 and 43.The contact point 41 now engages the detent recess 72b in the contactorIt will be recognized that the contactor 34 can be rotated in theopposite direction so that the contact point 41 will engage the detentrecess 720. In that case, the contact segments 82c and 82b on thecontactor 34 engage the contact points 42 and 43, respectively. Thus,the contactor 34 forms a closed electrical circuit between the contactpoints 42 and 43.

It will be understood that the contact points 42 and 43 may be connectedto the primary circuit of the ignition magneto so that the closure ofthe electrical circuit between the contact points 42 and 43 will shortcircuit the primary circuit. In this way, the magneto will beinactivated so that no spark will be produced by the magneto.Accordingly, the engine will be stopped.

As previously indicated, the electrical leads or wires 42a and 43a maybe connected to the contact points 42 and 43. The leads 42a and 43a mayextend to the primary circuit of the magneto, or any other circuit whichis to be controlled by the switch.

In this case, it is not necessary to connect an electrical lead to thecontact point 41, which is in contact with the contactor 34 in all threepositions of the contactor. However, in some cases, it may be desired toproduce a three-way make in the OFF positions, in which case anotherelectrical lead may be connected to the contact point 41. Such athree-way make is desirable, for example, when there are two magnetos orother devices which need to be inactivated.

As shown in FIG. 3, the stop members 86a and 86b may take the form oftip elements or portions on the removable pin 30. FIG. 11 shows theeffect of removing the pin 30 when the contactor 34 is in its RUNposition. The stop elements 86a and 86b are no longer present to holdthe contactor away from the contact points 42 and 43. Consequently, theforce exerted by the resilient means or spring 52 causes the contactor34 to move toward the contact points 42 and 43 until the recessedmembers 84a and 84b come into electrical engagement with the contactpoints 42 and 43. Thus, the contactor 34 completes an electrical circuitbetween the contact points 42 and 43 so that the engine of the vehiclewill be stopped.

In moving against the contact points 42 and 43, the contactor rocksabout the pivotal support afforded by the contact point 41 so that thecontactor extends at a slight angle to its normal orientation, as willbe evident from FIGS. 7 and 11.

It is preferred to provide means for detaining the removable pin 30against accidental withdrawal from the switch 10. As shown to bestadvantage in FIGS. 5-7, the pin 30 is adapted to be inserted into theswitch through a lateral opening 90 formed between the casing 20 and asegmental member 92 projecting from the contact supporting plate ormember 38. It will be seen from FIG. 3 that the stop elements 86a and86b take the form of prongs on the pin 30. A slot or notch 94 is formedbetween the prong elements 860 and 8612.

In this case, detent elements or barbs 96a and 96b project laterallyfrom the edges of the prong elements 860 and 86b. These detent elements960 and 96b are adapted to be detained by ribs 98 on the casing 20projecting into the opening 90 (FIG. 7). There is sufficientinterference between the detent elements 96a and 96b and the ribs 98 toretain the prong elements 860 and 86b in the opening 90 unlessconsiderable force is exerted on the pin 30 to pull it out of theopening. Because of the provision of the slot 94, the prongs 86a and 86bare sufficiently flexible to permit the removal of the pin 30 from theopening 90.

The exterior portion of the pin 30 preferably has a curved flangeportion 100 to form a snug closure for the opening 90. A hole 102 may beformed in the exterior portion of the pin 30 to receive the pull cord32.

It will be seen from FIG. 4 that the segmental member 92 on the contactsupporting member 38 is preferably formed with a pair of tongue elements104 adapted to interlock with grooves 106 on the casing 20. In this way,the casing is reinforced in the neighborhood of the opening 90 intowhich the pin 30 is inserted.

It will be understood that if the safety pull pin feature is not needed,the stop elements 860 and 86b of FIGS. 9 and 10 may be formed integrallywith the contact supporting member 38, as bosses thereon, or may beotherwise secured to the contact supporting member. The opening 90 forthe pin 30 may then be omitted. The switch will then operate in themanner described in connection with FIGS. 9 and 10 to provide a RUNposition, in which the contactor 34 does not engage the contact points42 and 43, and two OFF positions, in which the contactor engages thecontact points 42 and 43.

It will be understood that various mounting brackets or other devicesmay be provided to support the switch 10, rather than mounting itbetween the two parts 24 and 26 of the grip member 14, as shown in FIGS.1, 2 and 5.

As already indicated, various versions of the switch may be producedwith a variety of details as to detent arrangements and contact andcontactor constructions.

By way of illustration, a modified switch 110 is shown in FIGS. l62l.Many of the components of the switch 110 are the same as alreadydescribed. To avoid needless repetition of the description, thosecomponents of the switch 110, which are the same as previouslydescribed, have been given the same reference characters as previouslyemployed so that the previous description can readily be applied to suchcomponents. Thus, only the differences between the switch 110 and thepreviously-described switch 10 will need to be described in detail.

The switch 110 has a knob or handle 118 which is the same as thepreviously-described knob 18, except that the knob 118 is movablebetween two positions, designated HIGH BEAM and LOW BEAM in FIG. 16.These legends refer to the fact that the switch 110 is particularly welladapted for use as a headlight dimmer switch on a snowmobile or othervehicle. The switch 110 may employ the same casing 120 as previouslydescribed. The switch 110 has a contactor 134 which differs in detailfrom the previously-described contactor 34. These differences will bedescribed presently.

Likewise, the switch 110 has a contact supporting member or plate 138which differs in detail from the previously-described member 38. Thecontact points 41, 42 and 43 may be the same as previously described.

The detent arrangement may be very similar to that previously described.As shown in FIGS. and 21, the contactor 134 has the detent recesses orundulations 72a and 72c as previously described. However, the detentrecess 72b is omitted because the contactor 134 has only two operatingpositions.

To engage the contact points 42 and 43,'the contactor 134 preferably hasthree contact segments 182a, l82b and 1820, which are differentlylocated but otherwise are the same as the previously-described contactsegments 82a, 82b and 82c. Similarly, the contactor 134 has two recessedmembers or undulations 184a and 184b, which are differently located butotherwise are the same as the recessed members 84a and 84b, previouslydescribed.

Instead of the stop elements 86a and 86b, the switch 110 has stopelements 186a and l86b which are fixed to the contact supporting member138. Preferably, the elements 186a and 186b are formed as integralbosses on the contact supporting member 138.

Instead of the member 92, the contact supporting member 138 is formedwith a laterally projecting member 192 which is somewhat larger so as toclose the opening 90 in the casing 20. Such opening is not neededbecause the pull pin is not used.

In this case, the contact point 41 is provided with an electrical leador wire 141a. The leads 42a and 43a for the contact points 42 and 43 arethe same as previously described.

Instead of the inwardly projecting stop 74, the knob 118 is providedwith a larger stop 174 (FIG. 16) so as to restrict the rotary movementof the knob 118.

FIGS. 20 and 21 illustrate the operation of the switch 110. In FIG. 20,the contact point 41 is received in the detent recess 72a, and thecontact point is in electrical engagement with the contactor 134. Thecontact segment 182b engages the contact point 42 so that the contactor134 establishes an electrical circuit between the contact points 41 and42. On the other hand, the recessed member 18411 is opposite the contactpoint 43. The contact segment 182a engages the insulating boss or stop1861), which holds the contactor away from the contact points 43. FIG.20 represents the HIGH BEAM position of the knob 118.

When the knob is rotated to the LOW BEAM position, as shown in FIG. 21,the contact point 41 is received in the detent recess 720. The contactsegment 182!) engages the contact point 43 so that the contactor 134establishes a closed circuit between the contact points 41 and 43. Therecessed member 184a is now opposite the contact point 42. The contactsegment 182a engages the insulating boss or stop 186a, which holds thecontactor 134 away from the contact point 42.

In both positions of the switch, the contactor 134 has three points ofengagement with elements on the stationary supporting member 138 so thatthe contactor is completely stable, without any tendency to rock. In theposition of FIG. 20, the contactor engages the contact points 41 and 42and the insulating boss or stop 'the contact points 41 and 43 and thestop member 186a. The spring pressure is distributed among these threeelements so that positive contact pressure is maintained between thecontactor 134 and the contact points 41 and 43.

It will beevident that many versions of the switch may be produced byvarying the arrangement of the contact points, the contactor. the detentelements on the contactor, and the stop elements on the contactsupporting member. If desired, the stop elements can be replaced withdummy contact points which do not have external electrical connections.

In the switch 10 of FIGS. 115, the contactor 34 has three points ofengagement with the fixed elements on the contact supporting member 38,in all operating positions of the switch, as will be evident from FIGS.9, 10 and 11.

We claim:

1. An electrical switch,

comprising a casing,

a carriage rotatably mounted in said casing,

a contactor plate mounted on one end of said carriage and rotatabletherewith,

a plurality of contact points mounted in one end of said casing oppositesaid contactor plate for engagement by said plate, and

resilient means biasing said contactor plate toward said contact points,

said plate having a first portion conductively engaging a first one ofsaid contact points throughout the range of movement of said contactorplate,

said first portion having a plurality of angularly spaced recesses forreceiving said one contact point with a detent action whereby saidcontactor and said carriage are detained in positions corresponding tothe locations of said recesses,

said one contact point and said recesses being smoothly rounded andbeing of corresponding size such that said one contact point is snuglyreceivable in each of said recesses with a precise positioning action,

said contactor plate having a contact segment for engaging a second ofsaid contact points in at least one of said positions,

said contactor plate forming a closed electrical circuit between saidfirst and second contact points in at least one of said positions.

2. A switch according to claim 1,

in which said recesses are formed by undulations in said contactorplate.

3. A switch according to claim 1,

in which said one contact point is in electrical engagement with saidcontactor plate in each of said positions,

said contactor plate forming a closed circuit between said first andsecond contact points in one of said positions,

said contactor plate forming a closed circuit between said first contactpoint and a third of said contact points in another of said positions.

4. A switch according to claim 1,

in which said contact points include said first contact point and secondand third contact points,

said positions including first and second positions,

said first contact point being in electrical engagement with saidcontactor plate in both said first and second positions,

said contact segment engaging said second contact point in said firstposition while engaging said third contact point in said secondposition.

5. A switch according to claim 1,

in which said contact points include said first contact point and secondand third contact points,

said recesses in said contactor plate including first, second and thirdrecesses for receiving said first contact point in first, second andthird positions with a detent action,

said first contact point being in electrical engagement with saidcontactor plate in said first, second and third positions,

said contactor plate having contact segments for engaging said secondand third contact points in said second and third positions,

said contactor plate being out of engagement with said second and thirdcontact points in said first position.

6. An electrical switch,

comprising a casing,

a contactor in said casing,

means for rotating said contactor,

a plurality of contact points mounted in said casing opposite saidcontactor for engagement by said contactor,

resilient means biasing said contactor toward said contact points,

said contactor being rotatable to at least first and second positions,

said contactor having a contacting member for engaging at least one ofsaid contact points in said second position,

said contactor having a recessed member opposite said one contact pointin said first position,

and a stop member removably mounted in said casing and engageable withsaid contactor to hold said recessed member away from said one contactpoint in said first position,

said stop member being removable from said casing to cause movement ofsaid contactor by said resilient means to bring said recessed memberinto engagement with said one contact point, whereby removal of saidstop member causes closure of an electrical circuit between saidcontactor and said one contact point.

7. A switch according to claim 6,

in which said stop member takes the form of a removable pull pin,

said casing having an opening for receiving said pull pin.

8. A switch according to claim 7, including a tension member connectedto said pull pin for use in removing said pin from said casing.

9. A switch according to claim 6, v

in which said contactor includes a plurality of recessed members,

said contact points including at least two contact points opposite saidrecessed members when said contactor is in said first position,

said stop member having means engageable by said contactor to hold saidrecessed members away from said contact points in said first position,

said contactor having contacting means for engaging said contact pointswhen said contactor is in said second position.

10. A switch according to claim 9,

in which said recessed members take the form of undulations in saidcontactor,

said contacting means taking the form of contact segments on saidcontactor.

11. A switch according to claim 6,

in which said recessed member takes the form of an undulation in saidcontactor.

12. A switch according to claim 6,

in which said removable stop member is made of electrically insulatingmaterial.

13. A switch according to claim 6,

in which said means for rotating said contactor includes a rotatablecarriage in said casing,

said contactor being mounted on said carriage and being rotatabletherewith,

said resilient means comprising at least one spring acting between saidcarriage and said contactor.

14. A switch according to claim 13,

in which said contactor is plate-like in form,

said recessed member taking the form of an undulation in said contactor.

15. A switch according to claim 13,

in which said contactor includes at least two such recessed members inthe form of undulations in said contactor,

said contact points including at least two contact points opposite saidrecessed members when said contactor is in said first position,

said contact member having contact segments for engaging said contactpoints in said second position,

said removable stop member comprising means engageable by said contactorfor holding said recessed members away from said contact points in saidfirst position,

said stop member being removable to cause movement of said contactor bysaid resilient means to bring said recessed members into engagement withsaid contact points.

1. An electrical switch, comprising a casing, a carriage rotatablymounted in said casing, a contactor plate mounted on one end of saidcarriage and rotatable therewith, a plurality of contact points mountedin one end of said casing opposite said contactor plate for engagementby said plate, and resilient means biasing said contactor plate towardsaid contact points, said plate having a first portion conductivelyengaging a first one of said contact points throughout the range ofmovement of said contactor plate, said first portion having a pluralityof angularly spaced recesses for receiving said one contact point with adetent action whereby said contactor and said carriage are detained inpositions corresponding to the locations of said recesses, said onecontact point and said recesses being smoothly rounded and being ofcorresponding size such that said one contact point is snugly receivablein each of said recesses with a precise positioning action, saidcontactor plate having a contact segment for engaging a second of saidcontact points in at least one of said positions, said contactor plateforming a closed electrical circuit between said first and secondcontact points in at least one of said positions.
 2. A switch accordingto claim 1, in which said recesses are formed by undulations in saidcontactor plate.
 3. A switch according to claim 1, in which said onecontact point is in electrical engagement with said contactor plate ineach of said positions, said contactor plate forming a closed circuitbetween said first and second contact points in one of said positions,said contactor plate forming a closed circuit between said first contactpoint and a third of said contact points in another of said positions.4. A switch according to claim 1, in which said contact points includesaid first contact point and second and third contact points, saidpositions including first and second positions, said first contact pointbeing in electrical engagement with said contactor plate in both saidfirst and second positions, said contact segment engaging said secondcontact point in said first position while engaging said third contactpoint in said second position.
 5. A switch according to claim 1, inwhich said contact points include said first contact point and secondand third contact points, said recesses in said contactor plateincluding first, second and third recesses for receiving said firstcontact point in first, second and third positions with a detent action,said first contact point being in electrical engagement with saidcontactor plate in said first, second and third positions, saidcontactor plate having contact segments for engaging said second andthird contact points in said second and third positions, said contactorplate being out of engagement with said second and third contact pointsin said first position.
 6. An electrical switch, comprising a casing, acontactor in said casing, means for rotating said contactor, a pluralityof contact points mounted in said casing opposite said contactor forengagement by said contactor, resilient means biasing said contactortoward said contact points, said contactor being rotatable to at leastfirst and second positions, said contactor having a contacting memberfor engaging at least one of said contact points in said secondposition, said contactor having a recessed member opposite said onecontact point in said first position, and a stop member removablymounted in said casing and engageable with said contactor to hold saidrecessed member away from said one contact point in said first position,said stop member being removable from said casing to cause movement ofsaid contactor by said resilient means to bring said recessed memberinto engagement with said one contact point, whereby removal of saidstop member causes closure of an electrical circuit between saidcontactor and said one contact point.
 7. A switch according to claim 6,in which said stop member takes the form of a removable pull pin, saidcasing having an opening for receiving said pull pin.
 8. A switchaccording to claim 7, including a tension member connected to said pullpin for use in removing said pin from said casing.
 9. A switch accordingto claim 6, in which said contactor includes a plurality of recessedmembers, said contact points including at least two contact pointsopposite said recessed members when said contactor is in said firstposition, said stop member having means engageable by said contactor tohold said recessed members away from said contact points in said firstposition, said contactor havIng contacting means for engaging saidcontact points when said contactor is in said second position.
 10. Aswitch according to claim 9, in which said recessed members take theform of undulations in said contactor, said contacting means taking theform of contact segments on said contactor.
 11. A switch according toclaim 6, in which said recessed member takes the form of an undulationin said contactor.
 12. A switch according to claim 6, in which saidremovable stop member is made of electrically insulating material.
 13. Aswitch according to claim 6, in which said means for rotating saidcontactor includes a rotatable carriage in said casing, said contactorbeing mounted on said carriage and being rotatable therewith, saidresilient means comprising at least one spring acting between saidcarriage and said contactor.
 14. A switch according to claim 13, inwhich said contactor is plate-like in form, said recessed member takingthe form of an undulation in said contactor.
 15. A switch according toclaim 13, in which said contactor includes at least two such recessedmembers in the form of undulations in said contactor, said contactpoints including at least two contact points opposite said recessedmembers when said contactor is in said first position, said contactmember having contact segments for engaging said contact points in saidsecond position, said removable stop member comprising means engageableby said contactor for holding said recessed members away from saidcontact points in said first position, said stop member being removableto cause movement of said contactor by said resilient means to bringsaid recessed members into engagement with said contact points.